1. Field of the Invention
This invention relates to an electric power distributor for use in a motor vehicle which is adapted to distribute electric power supplied from a power source such as a battery incorporated in the motor vehicle to a plurality of electric load units equipped in the more vehicle.
2. Description of the Related Art
Heretofore, there has been known an electric connecting box, as a device for distributing electric power supplied from a power source incorporated in a motor vehicle to a plurality of electric load units equipped in the vehicle. The electric connecting box is constructed in such a manner that a number of substrates each mounted with a bus bar are placed one over another to form a distributing circuit, and various elements such as a fuse and a relay switch are provided on the circuit.
Recently, an electric power distributor has been developed to make such an electric connecting box smaller and to accomplish a high-speed switching control. Such an electric power distributor has an arrangement in which semiconductor switching elements such as field effect transistors (FETs) are provided between input terminals and output terminals of the power distributor in place of a relay switch to allow a control circuit of a control circuit board to control on and off of electric current supply.
For instance, Japanese Unexamined Patent Publication No. 10-126963 discloses an arrangement of such a power distributor in which a plurality of semiconductor switching elements (chips) are mounted on a control circuit board, current on/off control terminals (control signal input terminals) of the semiconductor switching elements are connected to a control circuit of the circuit board, input terminals provided at an appropriate position of the respective semiconductor switching elements for supplying electric current are connected to a common metal plate which is connected to a power source for receiving power therefrom whereas output terminals provided at an appropriate position of the respective semiconductor switching elements are connected to bus bars provided in an electric connecting box for outputting power to respective electric load units which are connected to the bus bars.
In the arrangement of the above publication, substrates each mounted with a bus bar thereon are required, in addition to the control circuit board on which the semiconductor switching elements are mounted. Further, these substrates are accommodated in a dedicated casing or box which is made of a material different from that for the control circuit board and the substrates mounted with the bus bars. In addition, connectors for connecting the input terminals and the output terminals to an external circuit provided outside the casing are required inside the box. Thereby, the power distributor as a whole becomes large, and internal wiring for connecting the terminals and the connectors becomes complicated.
It is an object of the invention to provide an electric power distributor which is free of the above problems residing in the prior art.
According to an aspect of the invention, an electric power distributor is mountable on a motor vehicle for distributing power from a power source installed in the motor vehicle to a plurality of electric load units equipped in the vehicle. The power distributor is provided with an input conductive strip formed with an input terminal at one end thereof, a plurality of output conductive strips each formed with an output terminal at one end thereof, an insulating holder for holding the input conductive strip and the output conductive strips on the same plane, and a plurality of semiconductor switching elements each including an input terminal connected to the input conductive strip and an output terminal connected to a corresponding output conductive strip to control on and off of electric current supply between the input conductive strip and the output conductive strip in accordance with an external control signal. The input terminal and the output terminals are projected in the same direction substantially orthogonal to the plane of the insulating holder.
An inventive electric power distributor is in a compact size, and enables distribution of electric power to a plurality of electric load units without complicated internal wiring.
These and other objects, features advantages of the present invention will become more apparent upon a reading of the following detailed description and accompanying drawing.